Hello Nataša Kažemaka,
Thank you for posting your query on Microsoft Q&A.
As per the description, we understand that you used to connect to Supermetrics with Microsoft Advertising Account and recently when you change password you are not able to login to the application. As suggested by the team you have added the application in your tenant and now it is asking for admin consent.
When you integrate any application in Entra ID tenant and when a user is trying to access the application, it will ask for user consent or Admin Consent as per the permissions required on Entra ID tenant.
When you grant tenant-wide admin consent to an application, you give the application access to the permissions requested on behalf of the whole organization. Granting admin consent on behalf of an organization is a sensitive operation, potentially allowing the application's publisher access to significant portions of your organization's data, or the permission to do highly privileged operations.
By default, granting tenant-wide admin consent to an application allows all users to access the application unless otherwise restricted. I suggest you reach one of your Global Administrators in your tenant to provide admin consent for the application. He needs to login to Entra ID portal and browse to Identity > Applications > Enterprise applications > All applications.
Here, select Supermetrics application
Select Permissions under Security.
Carefully review the permissions that the application requires. If you agree with the permissions the application requires, select Grant admin consent.
I hope this information is helpful. Please feel free to reach out if you have any further questions.
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